its easy to understand how SE view meta keywords - they ignore them, they haven't been used for a long time so I wouldn't get concerned over the length in fact I've added any meta keywords onto sites for a good few years

I think the big 3 google, yahoo & msn (bing) place very little weight or next to no weight on the meta keyword tag or the ammount of keywords placed in it. I personally use it as a reference for my keyword list for each page on a site. it doesn't help but it wont hurt either to have it.

Keyword Meta tag does not impact in Google's search engine ranking. Having a good Title and Meta Description Tag is more imperative, nevertheless it would not be totally wrong to have the meta keywords in place, just as a routine.

The internet is filled with people who speak different languages; therefore it is imperative to know how to optimize a site that is not drafted in English. For sites that are not written in the English language, you should include a Meta tag for languages. This improves your search engine optimization since engine spiders will understand the language that the website is written in.

Other than optimizing your major keyword phrases, you should also choose secondary keywords to work on. Remember not to use your secondary keyword too much otherwise you will end up overshadowing your primary keyword thus affect your search engine optimization marketing strategy. The recommended percentage for secondary keywords should be between 1 and 2 of the body content.